Hi everyone. I'm looking for a bit of help please. My wife drives a zafira and recently it started to loss power and EML comes on after 3 or 4 miles driving. The crank shaft sensor has been replaced and it drives a bit better but when idling the engine seriously hunts causing lots of vibration. When you take of in first gear the car will nearly stall. This will happen through first and second and into third. Once you reach about 45 mph it improves a little. Also when the car is switched of the EML will go off and car will have full power until EML comes back on. Any ideas where to go from replacing the crank shaft sensor.

I had the crank shaft sensor replaced on my 2002 2.0dti Zafira as it was hunting when idle. The engine kept reving up and down as if it was about to stall. After the sensor was replaced the problem went away but I noticed a loss of power as if the turbo was not working. When the engine was first switched on the EM light (with spanner) was not on but after a few minutes it would light and the loss of power would be more noticable. I took the car back to the garage and we opened the bonnet to find the mechanic had pulled a white pipe between the engine block and air intake out by mistake. He pushed it back in and after a few minutes the EM light went off. Engine power is back to normal and no problems since.

as posted above check all the vac pipes and i mean all, some of the pipes go to the heater, usuall culprit is a split connector on the valves/pump ( on end of head driven by the cam) turbo, egr (if vac opperated) also inspect the plastic pipes they rub and leak if these pipes are all okay post back and i will point you into the next area to check

Hi
Had a similar sort of problem on my petrol zafira not so long ago, and had my local garage do the fault test, however these are not a hundred percent accurate, as it told me the lambda sensor was not operating properly, got one ,fitted it but fault can back after a few miles, garage reset computer several times as it kept coming up with same codes, in the end we took a stab in the dark and slaved in a known working mass air flow meter, and ran car for a week with no reoccuring faults, put a new one in and alls been fine since then.
wouldn't advise getting a third party one for £30 as they can be suspect, you can get genuine vauxhall ones of the web for a lot less than the dealer
hope this helps
regards ray

Found this post very helpful led me straight to the problem which was loss of power and eml coming on and going into limp mode, very annoying!! I had changed the top intercooler hose because it was split, but still didn't sort the no boost, however I got lucky and just wiggled the connector on the boost pressure sensor and the eml has stayed off for now. I also disconnected the White vacuum hose at both ends and started it up and that's how the eml went off, must have been a combination of the both. Saved me a sherwoods bill at least :-)